It is a strategy of our body. It had a purpose: to be able to move farther away from the lakes and streams in search of food. Therefore, humans evolved to drink less water. We learned how to keep it better.
This is the result of a study. It shows that the human body uses between 30% and 50% less water per day than primates. It is published in the journal Current Biology. Humans evolved into the low-flow model. Inform EurekaAlert.
Move away from the water
This enabled our ancestors of hunters and gatherers to move further away from streams and valleys in search of food. It is explained by lead author Herman Pontzer from Duke University, USA. “A great advantage when the first humans made their living in the arid landscapes of the savannah,” he says.
The water turnover of 309 people from different lifestyles was compared to that of 72 monkeys from zoos and sanctuaries.
They found that the average person processes about three quarts, or 12 cups, of water a day. A chimpanzee or gorilla living in a zoo suffers twice.
Pontzer recalls that the researchers were surprised by the results. Humans have an amazing ability to sweat. Per square inch of skin, “humans have ten times more sweat glands than chimpanzees,” says Pontzer. This allows a person to exercise about two liters during a one hour workout. But saving water for humans was real and not just dependent on where people lived or how physical they were.
In our noses
During human evolution, something changed that reduced the amount of water our bodies use every day. The next step, says Pontzer, is to determine exactly how this physiological change took place. One possibility lies ahead of us. Fossil evidence suggests that humans began to develop a more prominent nose around 1.6 million years ago with the onset of Homo erectus. Our cousins, gorillas and chimpanzees, have much flatter noses.
Our nasal passages help save water by cooling and condensing the water vapor in the exhaled air. It becomes liquid in our nose and can be reabsorbed there.
A big nose may have helped early humans retain more moisture with each breath. It is a riddle to solve. People evolved to drink less water, ”admits Pontzer. Figuring out exactly how we’re going to do it is the next step, and it’s going to be a lot of fun. “